<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>5行5列星星</title>
</head>
<body>
    <!-- <script>
        var str  ='';
        for (var i = 1; i <= 5; i++){ // 外层负责打印五行
           
            for (var j = 1; j <= 5; j++){ //里层负责一行打印五个星星
            str =  str + '★';
            }
            str = str + '\n'
        }
        // 如果一行打印完毕5个星星就要另起一行 换行符 \n
        console.log(str);
    </script> -->


    <!-- 打印n行n列的星星 -->
    
</body>
</html>